Damping Metric
Quantifying the energy dissipation of a material involves measuring the phase lag between the applied stress and the resulting strain. Calculating the loss factor delta allows designers to evaluate how well a substance absorbs vibration and converts it into heat. This value is the tangent of the phase angle and represents the ratio of the loss modulus to the storage modulus.
It is a dimensionless quantity that typically ranges from 0.01 for hard plastics to over 1.0 for high damping rubbers.
Dissipation Ratio
Calculating this metric provides a direct way to compare the noise reduction performance of different elastomer compounds. A higher value indicates that more energy is removed from the system during each cycle of deformation.
This Property
This behavior is highly sensitive to temperature and frequency as the material approaches its glass transition point. Near the transition, the internal molecular friction reaches a peak and the damping effect is maximized.
Frequency Sensitivity
Measuring the damping over a range of frequencies allows for the optimization of engine mounts and structural dampers. If the damping is too low, the system may suffer from resonance and fatigue. Designers use this data to ensure that vibrations are suppressed across the operating range of the machine.
